Recently, the living standards of people are greatly raised. To relieve the pressure from work, people pay higher attention on leisure activities in their spare time in which barbecue is the most popular activity suitable for whole family members, relatives and good friends to join in. Particularly, among European or American families who own spacious garden, barbecue has become the most basic leisure and social activity. Therefore, most European or American families pay great and particular attention to a variety of rotisseries required in barbecue activities.
Referring to FIG. 1, the common rotisserie of rotary type 60 in the market is provided with a roast stove 61  shaped in cross section. Inside the roast stove 61 there is provided an accommodation space 611 to accommodate barbecue members such as a barbecue net, a gas stove or pieces of charcoal (not shown). A holding bracket 62 and another holding bracket 63 on which a motor seat 64 may be mounted are respectively provided on both opposite side walls of the roast stove 61. A rotary shaft hole 642 is provided on one side of the motor seat 64. Inside the motor seat 64 there is provided a motor (not shown) which is supplied with electricity required in normal operation through a power supply wire 643 to drive a rotary shaft (not shown). A fork rod 70 may be inserted into the rotary shaft hole 642 corresponding to the rotary shaft. One end of the fork rod 70 connects with the rotary shaft while the other end of the fork rod 70 rides over a notch 624 of the holding bracket 62. A pair of claws 651 are provided on a suitable position thereof whereby after an object to be roasted 80 (a whole chicken as shown) is forked and fixed by the fork rod 70 and the claws 651, the motor seat 64 can drive the fork rod 70 to rotate. The object to be roasted 80 is rotated and roasted through the gas or charcoal inside the roast stove 61.
Though so, the barbecue activity is normally arranged to proceed in a good weather or circumstance. However, the weather is unpredictable. Particularly, in spring or summer when the barbecue activities proceed frequently, under the convection effect of the front and the cloud system, the barbecue activities originally arranged to proceed in normal weather will often be interrupted or stopped by an unexpected heavy rain. Variety of roasting foods too late to be gathered up may be uneatable after getting soaked in the rain. The charcoal on roasting may be out of use after exposing to the rain. Although the barbecue activity will be spoiled by such situations, however the worst to be worried is that after the rotisserie of rotary type 60 gets soaked, rain water will splash or seep into the motor seat 64 along the hole or gap of the motor seat 64 to incur the problem of short circuit or electricity leakage of the motor and circuit inside the motor seat 64. Such short circuit or electricity leakage may endanger the user's property or body. Furthermore, since in European countries or USA where the barbecue activity is popular, the household uses a voltage of 220˜240 volts, once short circuit or electricity leakage occurs, the harm to the user will get more serious. Therefore, recently a few countries made safety rules for regulating outdoor electric appliances and requiring them to have waterproof function.
In view of the above, the inventor has designed and manufactured a waterproof motor seat as shown in FIG. 2 to solve the problems of short circuit and electricity leakage. The waterproof motor seat comprises a housing 10, a cover body 20 and a motor 30. On one side of the housing 10 there is provided an opening 11 in which an accommodation space 111 is formed for the motor 30 to be fixed therein. A waterproof washer 12 made of elastic material is provided on the end edge of the housing 10 adjacent to the opening 11. A groove 121 is cut on one side of the waterproof washer 12 facing the housing 10 for the waterproof washer 12 to sleeve on the end edge of the opening 11. A plurality of screws 40 pass through the corresponding holes 22 provided on the cover body 20 to fix the cover body 20 onto the housing 10. The cover body 20 covers the other side of the waterproof washer 12 and its end edge 21 abuts against the outer edge of the waterproof washer 12 so that when the cover body 20 and the housing 10 are joined into one body, both sides of the cover body 20 respectively attach to the cover body 20 and the housing 10 to attain a watertight position. A rotary shaft hole 23 is formed on the cover body 20 at a position corresponding to an axle seat 31 of the motor 30. A waterproof collar 25 is embedded in the periphery of the rotary shaft hole 23. When the cover body 20 and the housing 10 are joined into one body, the inner edge of the waterproof collar 25 can watertightly abut against the outer edge of the axle seat 31 and the groove 251 on the outer edge of the axle seat 31 can watertightly abut against the periphery of the rotary shaft hole 23 while the rotary shaft 32 can extend outside of the rotary shaft hole 23 from the axle seat 31.
Although the waterproof motor seat as shown in FIG. 2 has waterproof effect to some degree, in the process of actual production and assembly, the groove 121 provided on one side of the waterproof washer 12 facing the housing 10 is required to be configured and dimensioned to allow it to be precisely sleeved on the end edge of the opening 11 of the housing 10. Furthermore, when the cover body 20 is fixed onto the housing 10 by means of these screws 40, the end edge 21 of the cover body 20 is also required to be precisely abutted against the outer edge of the waterproof washer 12 so that when the cover body 20 and the housing 10 are joined into one body, both sides of the waterproof washer 12 will respectively attach to the cover body 20 and the housing 10 to attain a watertight position. However, the inventor finds that in the process of actual production and assembly, the elasticity of the waterproof washer 12 or the insufficiency of production precision will often make the groove 121 difficult to align with the end edge of the opening 11. The assembly operators will carelessly fix the cover body 20 onto the housing 10 when the groove 121 doesn't align with the end edge of the opening 11 yet. Consequently, the waterproof washer 12 will deform between the cover body 20 and the housing 10 as a result of which the inner wall of the groove 121 can not evenly and watertightly contact with the surface of the end edge of the housing 10 and thus a gap is formed therebetween. Finally, the waterproof washer 12 can not fulfill its supposed waterproof effect.